Delenn goes to Minbar to discuss her relationship with Sheridan, and is tested. Franklin and Marcus go to Mars to contact the rebels there. "I cannot have an aide who will not look up. You will be forever walking into things."

-Zach Allen is fitted for his uniform as new chief of security (and he's not excited about it since it means Garibaldi isn't returning to the post). He insults Minbari fashion sense, so the Minbari tailor stabs him with a needle; he complains it was on purpose; Lennier agrees and talks to the tailor in Minbari. Zach thinks the tailor is being told off; instead, Lennier says "Good work. Give me a moment with the Human, and next time... use a bigger needle."
-Ivanova is busy dealing with a Drazi festival. She is, once again, mildly injured.
-A member of Delenn's clan, Callenn, arrives to take her back to Minbar to answer for the charges that her relationship with Sheridan degrades all Minbari. She tries to leave secretly, but Lennier catches her and insists on coming with her, since he knows that the outcome of this trial may mean she never returns to B5.
-G'Kar is fitted with a human prosthetic eye (and which is therefore the wrong colour). It can transmit remotely and must be taken out nightly for recharging; Franklin encourages him to turn the eye off before taking it out, as it can otherwise be disorienting.
-Delenn, in a spangly black Earth dress, invites Sheridan to her quarters. The Minbari woman where a woman watches her prospective partner in his sleep for three nights has not been completed; they did one night aboard the White Star, one just before Sheridan left for Z'ha'dum, and she wants to complete the final night now. Why? Well, she needs to go to Minbar tomorrow. When will she be back? Uh, hard to say! Sheridan is busy but notes Delenn thinks this is important (and is holding back), and so agrees.
-Because of the ongoing propaganda war, Sheridan feels that he must try to make contact with other rebels before they lose all credibility. So he's sending Franklin (a little-known member of the command staff; not easily recognized) and Marcus (bodyguard) to make contact. The mission will take a long time because they need to plot a discreet, roundabout path to Mars to avoid various blockades.
-Delenn's trial: she's engaging in an heretofore unheard of relationship with an alien, all without her clan's approval. She is to undergo the trial known as The Dreaming, to tease out her true motivations, as they are not sure it is realling the 'calling of her heart'. Lennier is her protector.
-Delenn and Lennier drink some hallucinogenics and go on a trip. Delenn has done this once before, as Dukhat's Protector. She was terrified, and we see Dukhat telling her the only thing that can cause fear in the Dreaming is fear you have already brought with you.
-It then flashes forward to Dukhat dying on a Minbari ship as Delenn clutches his body and screams. As we know from previous episodes, the unfortunate death of Dukhat started the Earth-Minbari war. We did not know that Delenn was actually there.
-Flashback: on the same ship, Dukhat asking the acolyte Delenn about contacting the Humans -- a primitive, emotional race. The Workers don't want more possible resource sources, lest it weaken their position; the Warriors don't want to contact a primitive race; the Religious caste doesn't want alien pollution. Dukhat asks her opinion: well, the most dangerous threat is an unknown threat; shouldn't we at least get to know them a little? Dukhat agrees, but admits that the idea of contacting humans is too unpopular now and "authority should never be used as a club, Delenn." By involving her in this discussion, he has made enemies for her:

Dukhat: When others do a foolish thing, you should tell them it is a foolish thing. They can still continue to do it, but at least the truth is where it needs to be. They will be most upset with you now. You have embarrassed them. I apologize for that. In my anger, I believe I may have caused you more problems in the future.Delenn: No. No, Master... it is an honour. Dukhat: Don't interrupt when I'm being kind. It does not happen often, Delenn. Raise your eyes and look at me.Delenn: [keeping her gaze averted] ...It is disrespectful.Dukhat: I cannot have an aide who will not look up. You will be forever walking into things.

...with this last line a direct quote of something Delenn says to her new aide, Lennier, in the s1 episode Parliament of Dreams.
-Flashforward: Delenn is inducted into the Grey Council. This is the day that Dukhat dies. Dukhat congratulates her, but Delenn notes something is off -- and he admits that the Triluminary, normally inactive, glowed when she held it. It confirms something he had suspected, and is part of the reason he chose her as an acolyte -- but he is interrupted by an alarm.
-The alarm? Human ships have come into range of the Grey Council ship. THEY have decided to make first contact. But neither group understands the other's language, and Delenn notes a very ominous sign in the distance: Soul Hunter ships are approaching. There will be deaths, here.
-Dukhat realizes something: the humans will misunderstand why the Minbari ships are approaching with gun ports open. To Minbari, it is a sign of respect; the humans are likely to interpret it as an aggressive action. He orders them closed, but too late: the humans fire on the Valen'Tha. Dukhat dies, whispering something to Delenn that we cannot hear.
-It turns out the Council was divided as to how to respond: four for war; four against. Delenn, furious about Dukhat's death, votes for a total war. Let Earth be destroyed. "No mercy!"
-Delenn deeply regrets this action, and how her rage spread like fire through the Minbari. This prevented them from stopping the war even as her rage subsided.
-Delenn knows that this means her clan will interpret her relationship with Sheridan as part of her decade-long work to atone for her one mistake, which lead to so much suffering. And, indeed, Callenn comes in and declares the Dreaming ended. Delenn returns to her quarters, and tries to remember what Dukhat had whispered to her...
-Delenn slips out of her chambers and imbibes the hallucinogenics. Lennier does as well. Callenn confronts them; The Dreaming is closed. Delenn says she goes to seek the truth, and invites him to join her. He drinks as well. This time they hear Dukhat's words: "You are a child of Valen."
-Lennier, un, 'frees' Delenn's genealogy scroll, proving this.
-Why this matters: by this point, Delenn and the Grey Council know that Valen was actually Sinclair, who was not a pure Minbari. But Minbari beliefs rest on the idea of Minbari racial purity; the revelation that their prophet was part-human would shatter them. His children, after they returned from a period of persecution, integrated into Minbari society and themselves bore children. Callenn is currently kinda screwed: he can't let this secret come out, but this of course means Delenn is in the right--she's not even pure Minbari, she was already part Human before transforming. He finally offers a hail mary option: a pre-Valen tendency to marry two members of the opposing side of a conflict after the war had ended, representing reconciliation. She considers this proposal and leaves to fall into Sheridan's arms...
-Onboard their smuggling vessel, which is low on comfort, Marcus opens and closes his Denn'Bok (Minbari fighting stick) over... and over... and over..., driving Franklin insane. He asks Marcus to stop; Marcus instead starts singing "I am the very model of a modern Major-General"...